Linked Life Data

2168528

Source:http://linkedlifedata.com/resource/pubmed/id/2168528

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-10-10
pubmed:abstractText
Increasing evidence suggests that atrial natriuretic peptide (ANP), a 28 amino acid peptide with biologically active 4-28 and 5-28 congeners, modulates salt-water homeostasis at both peripheral and central levels. In rats, immunoreactive (ir) ANP is found in hypothalamic (HT) neurons of preoptic and paraventricular regions rich in aminergic innervation. Employing a well-characterized perifusion model of rat HT explants, the acute effects of norepinephrine (NE) on HT release of irANP were examined. Pulsatile administration (20 min) of NE (10(-7) to 10(-5) M) induced a dose-related release of irANP. The stimulatory effect of 10(-5) M NE (2.66 +/- 0.54 pg/ml/HT, means +/- SE, n = 12) was abolished in the presence of 10(-7) M propranolol, a beta-antagonist, but was 50% higher when administrated with 10(-5) M phentolamine, an alpha-antagonist. Administration of equivalent doses of propranolol or phentolamine alone, consistently suppressed (40% below basal secretion rate, BSR) or stimulated (50% above BSR) irANP release, respectively. In addition, infusion of isoprenaline (10(-5) M), a beta-agonist, enhanced BSR by 45%, whilst phenylephrine (10(-5) M), an alpha-agonist, suppressed it by 25%. We conclude that in rat hypothalami (1) occupancy of the beta-adrenoceptor by its agonist stimulates irANP release, (2) alpha- and beta-adrenoceptors modulate irANP secretion in an opposing manner, and (3) the basal release of irANP is a product of the activation of alpha- and beta-adrenoceptors by their endogenous ligands.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0028-3835
pubmed:author
pubmed:issnType
Print
pubmed:volume
52
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
65-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Hypothalamic atrial natriuretic peptide secretion plasticity: differential modulation of alpha and beta adrenoceptors.
pubmed:affiliation
Mental Health Research Institute of Victoria, Royal Park Hospital, Parkville, Australia.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro